<template>
  <div class="star" :class="starType">
    <span v-for="itemClass in itemClasses" :class="itemClass" class="star-item" :key="itemClass"></span>
  </div>
</template>

<script>
const LENGTH = 5;
const CLS_ON = 'on';
const CLS_HALF = 'half';
const CLS_OFF = 'off';

export default {
  props: ['size', 'score'],
  computed: {
    starType() { // starType是拼出来的一个类型，然后就可以根据不同的starType来定义不同的样式了
      return 'star-' + this.size;
    },
    itemClasses() {
      let result = [];
      let score = Math.floor(this.score * 2) / 2;
      let hasDecimal = score % 1 !== 0;
      let integer = Math.floor(score);
      for (let i = 0; i < integer; i++) {
        result.push(CLS_ON);
      }
      if (hasDecimal) {
        result.push(CLS_HALF);
      }
      while (result.length < LENGTH) {
        result.push(CLS_OFF);
      }
      return result;
    }
  }
};
</script>

<style lang="stylus">
  @import "../../common/stylus/mixin.styl";

  .star
    font-size 0
    .star-item
      display inline-block
      background-repeat no-repeat
    &.star-48
      .star-item
        width 20px
        height 20px
        margin-right 22px // 每个星星之间的间距，根据设计稿来计算
        background-size 20px 20px
        &:last-child
          margin-right 0 // 最后一个星星没有右边的margin
        &.on
          bg-image('star48_on')
        &.half
          bg-image('star48_half')
        &.off
          bg-image('star48_off')
    &.star-36
      .star-item
        width 15px
        height 15px
        // margin-right 16px // 每个星星之间的间距，根据设计稿来计算
        margin-right 6px // 每个星星之间的间距，根据设计稿来计算
        background-size 15px 15px
        &:last-child
          margin-right 0 // 最后一个星星没有右边的margin
        &.on
          bg-image('star36_on')
        &.half
          bg-image('star36_half')
        &.off
          bg-image('star36_off')
    &.star-24
        .star-item
          width 10px
          height 10px
          margin-right 3px // 每个星星之间的间距，根据设计稿来计算
          background-size 10px 10px
          &:last-child
            margin-right 0 // 最后一个星星没有右边的margin
          &.on
            bg-image('star24_on')
          &.half
            bg-image('star24_half')
          &.off
            bg-image('star24_off')
</style>
